1. Field of the Invention
The present invention relates to an oscillator and an oscillation apparatus using the oscillator. More specifically, this invention relates to a base-grounded or gate-grounded oscillator with a quarter-wave open-circuit terminal stub connected to the base or gate of a transistor and an oscillation apparatus using the oscillator.
Furthermore, the present invention relates to an oscillation apparatus, and more particularly relates to an oscillation apparatus with an oscillator and a resonator both of which are magnetically coupled.
2. Description of the Related Art
A conventional oscillator using a dielectric resonator has a circuit configuration shown in FIG. 7, for example. The oscillator 50 shown in FIG. 7 is called a band reflection type oscillator. In this type of oscillator, a transistor 51 for oscillation, such as a silicon bipolar transistor, is arranged on, for example, a dielectric substrate (not illustrated), and a stripline 52 is connected to the base. To the stripline 52, a DC cut-off capacitor 53 and a terminating resistance 54 are connected in series. Moreover, a dielectric resonator 55 is arranged in the vicinity of the stripline 52, and the arrangement causes the stripline 52 to be magnetically coupled to the dielectric resonator 55. Further, the collector of the oscillation transistor 51 is grounded. Also, the emitter of the oscillation transistor 51 is connected to the collector and base via respective capacitors. Here, the terminating resistor 54 functions to eliminate unwanted oscillation except the resonance frequency of the dielectric resonator 55. In addition, the internal and stray capacitance of the oscillation transistor 51 can be substituted for the capacitance between the emitter and collector and between the emitter and base of the oscillation transistor 51 shown in FIG. 7, and accordingly those capacitors are not generally formed as external components.
The oscillator 60 shown in FIG. 8 is called a reflection type of oscillator, in which an oscillation transistor 51, such as a silicon bipolar transistor, is arranged on, for example, a dielectric substrate (not illustrated). To the base of the transistor, a half-wave open-circuit terminal stub 61 is connected. Also, the collector of the oscillation transistor 51 is grounded. Further, the emitter of the oscillation transistor 51 is connected to the collector and the base via respective capacitors.
In addition, the internal and stray capacitance of the oscillation transistor 51 can be substituted for the capacitance between the emitter and collector and between the emitter and base of the oscillation transistor 51 shown in FIG. 8. As such, these capacitors are generally not formed as external components.